... PHP 4 >= 4.0.6) array_map -- Applies the callback to the elements of the given arrays . array array_map ( mixed callback, array arr1 [, array arr2...]) . ... function show_Spanish($n, $m) { return "The number $n is called $m in Spanish"; } function map_Spanish($n, $m) { return array ($n => $m); } $a = array(1, 2, 3, 4, 5); $b = array("uno", "dos", "tres", "cuatro", "cinco"); $c = array_map("show_Spanish", $a, $b); print_r($c); $d = array_map("map_Spanish", $a , $b); print_r($d); . ... array_keys . ...